Smoke ballpoint pens.
Smile -- All the time
Always flush the toilet three times.
Listen to radio static.
Open your window shades before you go to sleep each night. Close them as soon as you wake up.
Whenever you go to sleep, starts jumping on your bed . . . do so for a while, then jump really high and act like you hit your head on the ceiling. Crumple onto your bed and fake like you were knocked out . . . use this method to fall asleep...every night for a month.
Whenever his/her parents call and ask for your roommate, breathe into the phone for 5 seconds then hang up.
Fake a heart attack. When your roommate gets the paramedics to come, pretend nothing happened.
Whenever the phone rings, get up and answer the door
Whenever someone knocks, answer the phone.
Spend all your money on Transformers. Play with them at night. If your roommate says anything, tell him/her with a straight face, "They're more than meets the eye."
Get some hair. Disperse it around your roommate's head while he/she is asleep. Keep a pair of scissors by your bed. Snicker at your roommate every morning.
Trash your room when your roommates not around. Then leave and wait for your roommate to come back. When he/she does, walk in and act surprised. Say, "Uh-oh, it looks like THEY were here again."
Set your roommate's bed on fire. Apologize and explain that you've been watching too much Beavis and Butthead. Do it again. Tell him/her that your not sorry because this time they deserved it.
Eat lots of Lucky Charms. Pick out all the yellow moons and stockpile them in the closet. If your roommate inquires, explain that visitors are coming, but you can't say anything more, or you'll have to face the consequences
Draw a tiny, black spot on your arm. Make it bigger every day. Look at it and say, "It's spreading, it's spreading!"
Buy a McDonald's Happy Meal for lunch every day. Eat the straw and the napkin. Throw everything else away.
Buy a plant. Sleep with it at night. Talk to it. After a few weeks, start to argue with it loudly. Then yell, "I can't live in the same room with you," storm out of the room and slam the door. Get rid of the plant, but keep the pot. Refuse to discuss the plant ever again.
Buy a Jack-In-The-Box. Every day, turn the handle until the clown pops out. Scream continuously for twenty minutes
Pile dirty dishes in your roommate's bed. Insist that you don't know how they got there
Collect hundreds of pens and pile them on one side of the room. Keep one pencil on the other side of the room. Laugh at the pencil
While your roommate is out, glue your shoes to the ceiling. When your roommate walks in, sit on the floor, hold your head, and moan
Collect potatoes. Paint faces on them and give them names. Name one after your roommate. Separate your roommate's potato from the others. Wait a few days, and then bake your roommate's potato and eat it. Explain to your roommate, "He just didn't belong."
Move everything to one side of the room. Ask your roommate if he/she knows how much an elephant weighs, and look at the floor on the empty side of the room with concern
Every time your roommate comes in, immediately turn off the lights and go to bed. When he/she leaves, get up and loudly yell, "Okay guys, you can come out now!"
Sit in front of a chess board for hours, saying nothing, doing nothing. Then look up and say, "I think this game goes a lot faster with two players."
Talk back to your Rice Krispies. All of a sudden, act offended, throw the bowl on the floor and kick it. Refuse to clean it up, explaining, "No, I want to watch them suffer."
Change the locks on the door. Don't let your roommate in unless he/she says the secret word. Change the secret word often. If your roommate can't guess the secret word, make him/her pay a tithe.
Scatter stuffed animals around the room. Put party hats on them. Play loud music. When your roommate walks in, turn off the music, take off the party hats, put away the stuffed animals, and say, "Well, it was fun while it lasted."
When you walk into the room, look at the roommate in disgust and yell, "Oh you're here!" Walk away yelling and cursing.
Buy a watermelon. Draw a face on it and give it a name. Ask your roommate if the watermelon can sleep in his/her bed. If your roommate says no, drop the watermelon out the window. Make it look like a suicide. Say nasty things about your roommate at the funeral.

(if anyone does this they are awesome)
Draw a chalk outline on the floor. When your roommate comes in, say, "Don't worry. It's not what you think." If he/she asks about it again, immediately change the subject.
Drink a cup of coffee every morning. When you finish it, gnaw on the mug for about ten minutes. Then look at your roommate, immediately put the mug away, and quickly leave the room.
Set up about twenty plants in an organized formation. When your roommate walks in, pretend to be in the middle of delivering a speech to the plants. Whisper to them, "We'll continue this later," while eyeing your roommate suspiciously.
Keep some worms in a shoe box. When doing homework, go and consult with the worms every so often. Then become angry, shouting at the worms that they're stupid and they don't know what they are talking about.
Wear a paper hat. Every time your roommate walks in, say, "Welcome to McDonald's, can I take your...Oh, it's just you." Take off the hat, sit, and pout.
Go through your roommate's textbooks with a red pen, changing things and making random corrections. If your roommate protests, tell him/her that you just couldn't take it anymore.
As soon as your roommate turns off the light at night, begin singing famous operas as loud as you can. When your roommate turns on the light, look around and pretend to be confused.
Whenever your roommate sneezes, go and hide in the closet for about an hour. Look around nervously for the rest of the day.
Sit and stare at your roommate for hours. Bring others in to join you. Eat peanuts, throwing a few at your roommate. Then say, "Boy, these zoos just aren't what they used to be."
Buy a gun. Clean it every day. One day, put a band-aid on your forehead, and refuse to discuss the gun ever again.
Insist that you are a vegetarian and protest anytime your roommate eats meat. Then leave "Slim Jim" wrappers on the floor and lie on the bed holding your stomach everytime your roommate walks in. If he/she asks about the wrappers, say you know nothing about them
Every time your roommate walks in yell, "Hooray! You're back!" as loud as you can and dance around the room for five minutes. Afterwards, keep looking at your watch and saying, "Shouldn't you be going somewhere?"
Put your glasses on before you go to bed. Take them off as soon as you wake up. If your roommate asks, explain that they are Magic Dream Glasses. Complain that you've been having terrible nightmares
Set up meetings with your roommate's faculty advisor. Inquire about his/her academic potential. Take lots of notes, and then give your roommate a full report. Insist that he/she do the same
"Drink" a raw egg for breakfast every morning. Explain that you are in training. Eat a dozen donuts every night
Every Thursday, pack up everything you own and tell your roommate you're going home. Come back in an hour and explain that no one was home. Unpack everything and go to sleep.
Every time you wake up, start yelling, "Oh, my gosh! Where the heck am I?!" and run around the room for a few minutes. Then go back to bed. If your roommate asks, say you don't know what he/she is talking about.
Hang up pictures of chickens all over the room. If your roommate eats eggs, yell at him/her and call him/her a cannibal.
Buy some knives. Sharpen them every night. While you're doing so, look at your roommate and mutter, "Soon, soon...."
Bring in potential "new" roommates from around campus. Give them tours of the room and the building. Have them ask about your roommate in front of him/her, and reply, "Oh, him/her? He/she won't be here much longer."
Feign a serious illness for two weeks. Have a priest come to your room and visit you. Write out a will, leaving everything to your roommate. One day, miraculously "recover." Insist that your roommate write out a will, leaving everything to you. Every time he/she coughs, excitedly say, "Oooh, are you dying?"
Live in the hallway for a month. Afterwards, bring all of your stuff back into the room and tell your roommate, "Okay, your turn."
Keep a tarantula in a jar for three days. Then get rid of the tarantula. If your roommate asks, say, "Oh, he's around here somewhere."
Tell your roommate, "I've got an important message for you." Then pretend to faint. When you recover, say you can't remember what the message was. Later on, say, "Oh, yeah, I remember!" Pretend to faint again. Keep this up for several weeks
Bowl inside the room. Set up tournaments with other people in the building. Award someone a trophy. If your roommate wants to bowl too, explain that he/she needs bowling shoes.
Walk backwards all the time. Then pretend to trip and hurt yourself. Fake an injury and go through a long, painful recovery. Start walking backwards again
Explain to your roommate that you're going to be housing a prospective student in the near future. One day, bring in a pig. If your roommate protests, hug the pig and tell your roommate that he/she hurt its feelings. Watch T.V with the pig, eating lots of bacon
Make a sandwich. Don't eat it, leave it on the floor. Ignore the sandwich. Wait until your roommate gets rid of it, and then say, "Hey, where the heck is my sandwich!?" Complain loudly that you are hungry
Punch a hole in the T.V. Sit and watch it anyway, complaining about the poor picture quality
Wear a cape. Stand in front of an open window for about an hour every day. Then, one day, when your roommate is gone, go outside and lie down underneath the window, pretending to be hurt, and wait for your roommate to return. The next day, start standing in front of the window again
Fill an empty shaving cream can with whipped cream. Use it to shave, and then spray some into your mouth. Later on, complain that you feel sick. Continue this process for several weeks.
Cover your bed with a tent. Live inside it for a week. If your roommate asks, explain that "It's a jungle out there." Get your roommate to bring you food and water.
Keep a vacuum cleaner in the middle of the room. Look at it with fear for a few days. Then stay out of the room entirely, opening the door only a crack and whispering to your roommate, "Psst! Is it gone?"
Break the window with a rock. If your roommate protests, explain that you were hot. Open and close the broken window as you normally would
Throw darts at a bare wall. All of a sudden, act excited, telling your roommate that you hit the bull's eye
Send flowers to your roommate, with a card that says, "I'm sorry. It won't happen again." When you see them, start ripping up the flowers. Repeat the process for a few weeks.
Call your roommate "Clyde" by accident. Start doing so every so often. Increase the frequency over the next few weeks, until you are calling him "Clyde" all the time. If your roommate protests, say, "I'm sorry. I won't do that anymore, Murray."
Hire a night watchman to guard the room while you are sleeping
When your roommate comes in, pretend that you are on the phone, screaming angrily and shouting obscenities. After you hang up, say, "That was your mom. She said she'd call back."
Start wearing a crown, all the time. If your roommate tells you to take it off, say, "What the heck do you think you are? A king?"
Trash everything your roommate owns, pack your bags, and before your roommate gets into the room, walk out of the door and say, "I'm never going back THERE again." and leave.
Turn out all the lights and put blankets over the windows so it is completely dark. When you roommate comes in, start to speak in tongues. When S/He turns on the light, scream and run under a desk/bed, whimper for a few minutes then come out and look at her angrily for the rest of the day.
Pile up dishes next to the door, when he walks in and breaks them, scream at him/her telling him/her that it was all his/her fault. Don't make eye contact for the rest of the day
Sit with your knees to your chin on your bed and whimper. When your roomate walks by and looks at you, say with fear almot inaudibly "S/He knows, S/he knows" until they leave.
Hum songs that will be stuck in their heads for weeks, like the barney songs . . . shudder . . .
Twitch a lot.
Pretend to talk while pretending to be asleep
Move you roommate's personal effects around. Start subtly. Gradually work up to big things, and eventually glue everything s/he owns to the ceiling.
Recite entire movie scripts almost inaudibly.
Get a computer. Leave it on when you are not using it. Turn it off when you are
Ask your roommate if your family can move in "just for a couple of weeks."
Keep asking, "Where's Waldo?"
Leave a declaration of war on your roommate's desk. Include a list of grievances.
Shoot rubber bands at your roommate while his/her back is turned, and then look away quickly
Dye all your underwear lime green
Dye all of your roommate's underwear lime green
Buy three loaves of stale bread. Grow mold in the closet
Hide your underwear and socks in your roommate's closet. Accuse him/her of stealing it
Remove your door. Ship it to your roommate's parents (postage due).
Whenever your roommate walks in, wait one minute and then stand up. Announce that you are going to take a shower. Do so. Keep this up for three weeks.
Array thirteen toothbrushes of different colors on your dresser. Refuse to discuss them
Paint your half of the room black.
Shave one eyebrow
Shelve all your books with the spines facing the wall. Complain loudly that you can never find the book that you want
Clip your fingernails and toenails and keep them in a baggie. Leave the baggie near your computer and snack from it while studying. If he/she walks by, grab the bag close and eye him/her suspiciously
Whenever he/she is about to fall asleep, ask questions that start with "Didja ever wonder why...." Be creative.
Whenever he/she goes to shower, drop whatever you're doing, grab a towel, and go shower too
Whenever your roommate brushes his/her teeth, watch him/her do so. Take notes. Write a paper on it, and circulate it around campus. If your roommate protests, say, "The people have a right to know!"
Wear your shoes on the wrong feet, all the time. Constantly complain that your feet hurt
Instead of turning off the light switch, smash the light bulb with a hammer. Put a new bulb in the next day. Complain often about the cost of light bulbs.
Hit your roommate on the head with a fly swatter. Claim that you were trying to kill a mosquito
When your roommate goes away for a weekend, change the locks
Hang a tire swing from the ceiling. Act like a monkey. If someone besides your roommate comes in, cease acting like a monkey and claim that the tire swing was your roommate's idea. When you and your roommate are alone again, continue acting like a monkey.
Challenge your roommate to a duel. If he/she refuses, claim that you have won by forfeit and therefore conquered his/her side of the room. Insist that he/she remove all of his/her possessions immediately.
Sign your roommate up for various activities (Campus tour guide, blood donor, organ donor).
(My own addition) Talk to yourself like Gollum does. Do this every night before you go to sleep. Refuse to answer any questions about it.
Done any of those?
This is too much for easily amused people like me